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Discussion Starter · #1 ·
Hi guys, I just got my 2014 gsxr 750. I'm getting 78miles for a full tank. The person I bought it from said he gets around 100-120 depending on how he rides. Only thing I did was swapped out the stock exhaust for a M4 slip on. Any idea what I'm doing wrong?
 

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Are you towing a full sized trailer? That seems very low

Are these highway miles or city miles? A lot of stop and go?

You should get closer to 150-175 depending on how you and where you ride

i4 sport bikes typically get high 30s to mid 40s in mpg. You are getting about 17mpg. Does the exhaust smell strong like gas? Does it sound normal when it runs?

You can also see if your brakes a dragging or if your tire pressure is low.
 

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Discussion Starter · #6 ·
Are you towing a full sized trailer? That seems very low

Are these highway miles or city miles? A lot of stop and go?

You should get closer to 150-175 depending on how you and where you ride

i4 sport bikes typically get high 30s to mid 40s in mpg. You are getting about 17mpg. Does the exhaust smell strong like gas? Does it sound normal when it runs?

You can also see if your brakes a dragging or if your tire pressure is low.
Hi. I mostly ride highway miles. When I am riding it dosent sound like it's running harder than it should and also dosent smell strong in gas. My tire pressure is good. It's at 34psi.

Maybe I am shifting at high rpms? I tend to shift around 10-12k. But I feel that's normal. I always rode r6s before this and I was getting atleast 120 per tank on the r6s.
 

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Hi. I mostly ride highway miles. When I am riding it dosent sound like it's running harder than it should and also dosent smell strong in gas. My tire pressure is good. It's at 34psi.

Maybe I am shifting at high rpms? I tend to shift around 10-12k. But I feel that's normal. I always rode r6s before this and I was getting atleast 120 per tank on the r6s.
Depends on how long you stay at high rpm. If you linger in 3rd or 4th on the highway you will waste gas. That still seems excessive. I wouldn’t attribute shifting higher to as much of a efficiency loss as you described, unless you are shifting a lot and at high rpm for extended periods of time
 

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Depends on how long you stay at high rpm. If you linger in 3rd or 4th on the highway you will waste gas. That still seems excessive. I wouldn’t attribute shifting higher to as much of a efficiency loss as you described, unless you are shifting a lot and at high rpm for extended periods of time
I think that might be the issue. I tend to catch myself riding in 3rd and 4th a lot on the highway. I'm going to ride casually this fill up and see if it is my riding style. I can say coming from an r6 to the 750 is a change. Atleast for me.
 

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I think that might be the issue. I tend to catch myself riding in 3rd and 4th a lot on the highway. I'm going to ride casually this fill up and see if it is my riding style. I can say coming from an r6 to the 750 is a change. Atleast for me.
Yeah if you aren't accelerating / don't plan on needing to accelerate there is no point in sitting in the powerband on the highway. You might as well sit in 6th and drop 2 gears when you need to.
 

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Discussion Starter · #10 ·
Yeah if you aren't accelerating / don't plan on needing to accelerate there is no point in sitting in the powerband on the highway. You might as well sit in 6th and drop 2 gears when you need to.
I appreciate the response. I'll definitely keep updated. I know there has to be something I'm doing wrong haha. Just the 750 is way smoother than the r6 where I don't feel like I'm still in the lower gears haha
 

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78 miles a tank full? have you determined how many gallons you're burning for that number? fill tank, set trip to zero, ride it, refill it, divide miles on trip meter by gallions you just put in..

are sprox stock size?

is it running rich as in is the tip of the exhaust can very black and sooty?

how about plugs, they should be tannish in color, not rich, not lean..

when exhaust flapper is removed it hurts MPG a little as does an aftermarket exhaust and pair removal, for instance, I installed a full system on a busa, it went from 44 to 38, lost around 6 mpg..

good grief you are getting what 18 mpg? not good for a 750, not good at all, nuther reason I leave em stock, they are at their most efficient state possible, aside form perhaps gearing up the sprox for better freeway mileage..

do the math here, tank holds 4.5 gallons, you're getting 17.3 MPG you should be getting twice that, you should be getting between 36 and 40 mpg on that bike..what octane are you running, a lot of folks say it doesn't matter but it does to a degree, for max efficiency you want to run the octane to match compression ratio..

look up in manual what manufacturer recommends, Hayabusa is low compression, it runs best on 87-88, however it is not a closed loop FI like your 750, its open, even tho detonation is more about ignition and valve timing closed helps a little to run what you want but a high compression engine on low compression gas isn't max efficiency.. however typically results are not even 1 MPG difference on closed loop systems usually definitely not 20 mpg loss..
 

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Discussion Starter · #12 ·
78 miles a tank full? have you determined how many gallons you're burning for that number? fill tank, set trip to zero, ride it, refill it, divide miles on trip meter by gallions you just put in..

are sprox stock size?

is it running rich as in is the tip of the exhaust can very black and sooty?

how about plugs, they should be tannish in color, not rich, not lean..

when exhaust flapper is removed it hurts MPG a little as does an aftermarket exhaust and pair removal, for instance, I installed a full system on a busa, it went from 44 to 38, lost around 6 mpg..

good grief you are getting what 18 mpg? not good for a 750, not good at all, nuther reason I leave em stock, they are at their most efficient state possible, aside form perhaps gearing up the sprox for better freeway mileage..

do the math here, tank holds 4.5 gallons, you're getting 17.3 MPG you should be getting twice that, you should be getting between 36 and 40 mpg on that bike..what octane are you running, a lot of folks say it doesn't matter but it does to a degree, for max efficiency you want to run the octane to match compression ratio..

look up in manual what manufacturer recommends, Hayabusa is low compression, it runs best on 87-88, however it is not a closed loop FI like your 750, its open, even tho detonation is more about ignition and valve timing closed helps a little to run what you want but a high compression engine on low compression gas isn't max efficiency.. however typically results are not even 1 MPG difference on closed loop systems usually definitely not 20 mpg loss..
So I pumped a full tank when my gas light came on and I WA sonly able to pump 2.7 gallons. Is that normal?
 

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nope, you aren't draining the tank that's the problem, your light is coming on right, does it have 1 or 2 lights, or does it just start flashing faster the lower it gets?

if the light is coming on then prolly the sensor in the tank needs adjusting?

does your bike have 2 warning lights or one, a gauge? one light tells you it's getting low and the other is reserve like half gallon remaining..

78 divided by 2.7 = 28.8mpg... better

did you happen to trip the meter to zero upon fill up?

if so ride it till the light comes on whatever then fill it, note how much it took, then zero again or use trip #2 and zero that

it could be the sensor is flopping loose or something and that you only used 1.75 gallons when you noted the 78 miles before? 29 mpg is better, but unless you have larger rear sprocket or smaller front, a very rich issue or a fuel leak it's still about 8-10 mpg off.. a pipe might do this? seems high to me for a middle weight but who knows maybe its running rich too?

how are you riding is it wall to wall railing or conservative/normal? balls to the walls it can be like 28, specially if you ride it high in the RPM's wall to wall, like on the track you might get 18 mpg or so cuz your on it all the time not even lifting to shift gears..

if you're riding like this which is common then 28 can be right..

why you hear a lot of people say "I am getting 27 mpg on my new 1000r" they're not taking into consideration riding style, on the freeway, 6th gear doing the speed limit they get 35+ or so, mid sized get like 38, the Busa however is a tall geared bike very low compression, has so much torque you can coast in 6th doing the speed limit and get 45 mpg.. the middle wights and liter bikes aren't geared as tall so they won't see that unless you add some teeth to the front or remove from the rear, and that only works on 750+ as the smaller CC's dont have the grunt and it actually works backwards, you have to shift down to 5th a lot and there goes the economy, they have the 600's geared about max for their torque, of course the 1000 has plenty of extra and the 750 has like 1 tooth maybe 3-4 mpg on top more..

if you're touring or commuting it all adds up tho, reel in that riding style, shift early and often then putt, never go over like 4-5k rpm on the 1k and over 6-7 on the middle weights, all stock you should see decent economy, specially if you burn the right fuel and stop eating all those dang bacon cheeseburgers and firehouse pizzas... :).. ask me how I know that!

set your trip meter wait till your light comes on and fill, ride normal till then, (5-10 over cagers pace) note capacity, zero out again...

do the math and if it's strange get back to us, you might have something off with the fuel level sensor, not sure how that one works if it has a float it may be bent or fubar somehow, most likely an easy fix, get 2 large alligator clips, and 2 pins, solder a clip to one end, pin to the other, heat shrink, 4-5 feet 14 gauge wire works, then disconnect your battery ground, unplug pump connector.. then clip + and - terminal to battery then use the pins to poke into the fuel pump connector corresponding pins to activate pump, (service manual wiring diagram) disconnect FI fuel line from tank, find a long hose to plug into tank nipple, pump out into can empty as much as you can..

remove 2 front bolts and the 4 rear on the chassis, unplug vent hoses so forth, remove tank, have a nice place to set it with cardboard and shop rags laid out so its soft and cushy, set down on cap side, (upside down) remove fuel pump carefully, maybe watch a video or see service manual, if it has a float they need to be threaded out not just yanked, could have been a bad install previously or just defective or failing? do this if the math/capacity is still off and you rode normally..

me thinks mid to upper 30's is about right with proper riding on this bike, octane, decent tune up, check air filter make sure its clean and maybe plugs eyeball how its mixing... blackish is too rich, whitish is too lean, tanish is about right..

post pics if its off, or just live with it, if you know you get 34 mpg and burn 2.4 gallons when the light comes on you know you have about 2 gallons left and a range of about 65 miles, use trip meter on each fill and keep it on top the clock, eyeball occasionally, basically the same thing you do on bikes with no fuel gauge, a lot of bikes do not have one... how its done, specially when there is no reserve.. :)

it runs fine right?
 

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Discussion Starter · #14 ·
nope, you aren't draining the tank that's the problem, is your light coming on or something?

if the light is coming on then it the sensor in the tank needs adjusting..

does your bike have 2 warnings, one tells you it's getting low and the other is reserve like half gallon remaining..

78 divided by 2.7 = 28.8mpg better

did you happen to trip the meter to zero upon fill up?

if so ride it till the light comes on whatever then fill it, note how much it took, then zero again or use trip #2 and zero that

it could be the sensor is flopping loose or something and that you only used 1.75 gallons when you noted the 78 miles, 29 miles is better, but unless you have larger rear sprocket or smaller front, a very rich issue ora fuel leak its still about 8-10 mpg off..

how are you riding is it wall to wall railing or conservative or normal? balls to the walls it can be like 28, specially if you ride it high in the RPM's wall to wall, like on the track you might get 18mpg or so cuz your on it all the time not even lifting to shift gears..

if you;re riding like this which is common then 28 is about right,

why you hear a lot of people say "I am getting 27mog on my new 1000r" they are not taking into consideration the riding style, on the freeway, 6th gear doing the speed limit they get close to 35 or so, mid sized get like 38, the Busa however is a very tall geared bike very low compression, has so much torque you can coast in 6th doing the speed limit and get 45mpg.. the middle wights and liter bikes are geared as tall so they wont see that unless you add some teeth to the front or remove from the rear, and that only works on 750+ as the smaller CC's dont have the grunt and it actually works backwards, you have to shift down to 5th a lot and there goes the economy, they have the 600's geared about mx for their torque, of course the 1000 has plenty of extra and the 750 has like 1 tooth maybe 3-4 mpg on top, if you are touring or commuting it all adds up tho, reel in that riding style, shift early and often then putt, never go over like 4-5k on the 1k and over 6-7 on the middle weights, all stock you should see decent economy, specially if you burn the right fuel and stop eating all those dang bacon cheeseburgers and firehouse pizzas... :).. ak me how I know that!

if you set your trip meter wait till your light comes on, ride normal till then, (5-10 over cagers pace) then fill and note capacity, zero out again...

do the math and if it's strange get back to us, you might have something off with the fuel level sensor, not sure how that one works if it has a float it may be bent or fubar somehow, most likely an easy fix, get 2 large alligator clips, and 2 pins, solder a clip to one end, pin to the other, heat shrink, 4-5 feet 14 gauge wire works, then disconnect your battery ground, unplug pump connector.. then clip + and - terminal then use the pins to poke into the fuel pump connector corresponding pins to activate pump, disconnect FI fuel line from tank, find a longe hose to plug into tank nipple, pump out into can as empty as you can get it..

remove 2 front bolts and the 4 rear on the chassis, unplug vent hoses so forth, remove tank, have a nice place to set it with cardboard and shop rags laid out so its soft and cushy, set down on cap side, (upside down) remove fuel pump carefully, maybe watcha video or see service manual, if it has float they need to be threaded out not just yanked, could have been a bad install previously or just defective or failing? do this if you do the math and its still low and you rode normally..

me thinks mid to upper 30's is about right with proper riding, octane, and decent tune up, check air filter make sure its clean and maybe plugs to key on how its mixing... blackish is too rich, whitish is too lean, tanish is about right..

post pics if its off, or just live with it, if you know you get 34 mpg and burn 2.4 gallons when the light comes on you know you have about 2 gallons left and a range of about 65 miles, use trip meter on each fill and keep it on top the clock, eyeball it occasionally, basically the same thing you do on bikes with no fuel gauge, a lot of bikes do not have one... how its done, specially when there is no reserve.. :)

it runs fine right?
Honestly I feel like I'm riding like I'm riding on the track. I shift at very high rpms. But the thing is that's how I rode with my r6 so I didn't think it was an issue. I had this bike for 2 full tank now and they both were around 78miles til the blinking gas light comes on.

My sprockets should be stock. I bought this bike from a buddy and he didn't do anything to the bike. He left everything stock. And he was getting over 100 a full tank. So I'm thinking either I'm killing the throttle or the tank sensor needs adjusting.
 

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sounds like your sensor is off then, inspect, it's in tank on fuel pump, or its working as it should and its just coming on letting you know you have less than half tank, maybe it blinks faster when you get down to a gallon or so, find a user's manual see what's what, or ask the dealer or someone here what's what with the fuel light, sounds like your riding style is like 28 mpg with a pipe so its a light thing and you actually have a few more gallons left in the tank..
 
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